The objectives of this study is to develop potent inhibitors of chemically induced carcinogenesis in animals and eventually to translate laboratory findings to human application. Selenium and sulfur containing compounds are known inhibitors of chemically induced carcinogenesis. We hypothesize that the inclusion of two well established functional groups in a single molecule would exert cumulative effect and thus would lead to the development of a new class of potent cancer chemopreventive agents. The evidence for this hypothesis comes from the results of the studies conducted in our laboratory on bifunctional inhibitors of chemical carcinogenesis. Eight novel bifunctional organoselenium compounds are designed. two typical members of this series have now been synthesized and characterized. The remaining six compounds will be synthesized, in a similar manner to evaluate their chemopreventive efficacy. The chemopreventive efficacy of the proposed compounds will be evaluated by five rapid screening bioassays. PROPOSED COMMERCIAL APPLICATIONS: The new products developed in this project will be of immense potential to combat cancer, and therefore, will be produced and marketed by LKT Laboratories as research chemicals to cancer researchers and to other fellow scientists.